Perhaps you should try some spelling variations:
dau tren » dau tien, dat tren, dau tieng
cau tren » cu tren, ca tren, cau treo
nhan luc » nang luc
hanh ke » hanh kem, thanh ke, hanh ky
va hanh » van hanh, va thanh, va danh
ve nhan » ve nha, de nhan, va nhan
hieu ve » hieu va, hieu van
nang xa » lang xa, nang ma, mang xa
sac ky » cac ky, sai ky
luc va » duc va, tuc va, loc va
tu sac » tu sach, tu cac, tu san

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: tu sac ky ((nang xa) or (nang x)) hoi. hieu ve nhan luc va hanh ke ((cau tren) OR (dau tren))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: tu sac ky ((nang xa) OR (nang x)) hoi. hieu ve nhan luc va hanh ke ((cau tren) OR (dau tren)).
• The words AND, OR and NOT may confuse the search; try adding quotes: "tu sac ky ((nang xa) or (nang x)) hoi. hieu ve nhan luc va hanh ke ((cau tren) OR (dau tren))".
• Adding a wildcard symbol may retrieve word variants: tu sac ky ((nang xa) or (nang x)) hoi. hieu ve nhan luc va hanh ke ((cau tren) OR (dau tren))*.